would it be possible to have different colors of the profile curve depending on the mix, just like displayed by OSTC in it's logbook ? I know, that there is a separate small graph below , which could show gas changes, but I would appreciate if the colors were represented with a small legend.

Thank you for the suggestion, I'll see if I can implement that. Even though I'm not sure if different colors will be really helpful. As you say, a legend is required to see the actual mixture, and that takes a lot of space and may cover the profile. During warnings the profile is already in red color, so that might cause confusion, too. And there are other features planned that have to be integrated into the main profile, so it might be too much in the end.

Actually You do not need a legend, since You can display it in the third graph that could serve as a legend itself.
Or, as an alternative, could the gas switch points be either customizable with a user-selected color, or be made more distinct from the curve ? Maybe with a small overlay text stating from which to which mix the change has been done ? Just like it happens on mouse over ...

The gas switch points in the main profile have already an overlay, just hover with your mouse over the point and you'll see it.

Kind regards,
Sven

Edit: Sorry, I just saw that you've already known that. Displaying all overlays all time didn't worked well during my testing. They may overlap when switches are very close and you can't read all of them and it looked very cluttered. I've tested a lot of different things with a lot of sample dive data I got from users and there are a lot of scenarious to consider so it looks nice for all kind of dives. But I'll see if it can be improved.

On the subject of gas changes. Is it possible for the red marker line to be extended across all Profiles.
For example I have a transmitter on my main tank so changing to my bailout or a second tank is easier to identify by tank pressure change than depth.

Maybe allow me to explain my point of view. I am aware of the gas mixes shown in the chart at the bottom, however, I wish my main profile graph was as useful as possible. Hence I would like to have either different colors of the graph OR nicely marked gas switch points. Maybe at least the color of big gas switch point could be changed from grey to something more distinct and immediately visible on the chart.

But the Divinglog software is already very good and I am very happy with. It is just an improvement suggestion

Just to ping on the subject. Any news on Your side on coloring or marking gas switches readable on the spot ?

If You are considered that overlays could be too close and may overlap - You could maybe put them on the side of the chart, and just point arrows/lines to the switch points ? Also, could You make switch points different color than gray ? Something that really stands out (but not RED, as it stands for danger). Please, please, please.

This is an excellent addition - thank you! Marking gas switches on the depth curve makes a lot of sense. For example, now gas switches are clearly visible when you print the log. Further, warning lines (e.g., deco info) can be displayed concurrently with the depth profile. This is really a great feature!